A UTM -> Lat/Long (or vice versa) converter.
Call setDatum with the index of the datum to be used and then call the various conversion functions latLngToUtm(), utmToLatLng() or natoToLatLng(), utmToNato(), natoToUtm() to convert between the various coordinate systems, hopefully accurately!
NOTE: no attempt is made to compensate for the irregular grid in the area around the southern coast of Norway and Svalbard (zones 32V and 31X, 33X, 35X and 37X) because of this results returned for NATO coordinates for lat/lng or UTM values located in these regions will not be correct.
This converter has been translated into python from the original javascript file develop at Montana University, which in turn was adapted from the script used at http://www.uwgb.edu/dutchs/UsefulData/ConvertUTMNoOZ.HTM